1. Field
The described technology relates generally to a polycrystalline silicon layer inspecting device and inspecting method. More particularly, the described technology relates generally to a device for inspecting crystallinity or crystal particles of a polycrystalline silicon layer, and an inspecting method thereof.
2. Description of the Related Art
Most flat panel display devices, such as an organic light emitting diode (OLED) display, a liquid crystal display (LCD), and the like, include a thin film transistor. Particularly, a low temperature polycrystalline silicon thin film transistor (LTPS TFT) having good carrier mobility can be applicable to a high speed operational circuit and can be used for a CMOS circuit, so the LPTS TFT has been commonly used.
The LTPS TFT includes a polycrystalline silicon film that is formed by crystallizing an amorphous silicon film. Methods for crystallizing the amorphous silicon film include a solid phase crystallization method, an excimer laser beams crystallization method, and a crystallization method using a metal catalyst.
Among various crystallization methods, a crystallization method using laser beams has been widely used because it enables a low temperature process so that a thermal effect on a substrate is relatively low and enables making a polycrystalline silicon layer having relatively excellent carrier mobility as high as over 100 cm2/Vs.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.